在叠加图像上绘制一个矩形

Question

我想在MATLAB(I和imagesc(data))中叠加两个图像,然后在这些图像上面绘制一个矩形.I2在以下代码中指定透明度模式.矩形在图像顶部变成一条线.谁能告诉我为什么矩形没有正确绘制？

imshow(I);           
hold on;
h = imagesc(data,[0,1]);    
hold off;
I2 = ones(height,width) * 80;
set(h, 'AlphaData', I2);
rectangle('Position',[100,100,20,20]);    

Answer 1

由于我们无法在没有所有数据的情况下完全重现您的代码,因此以下是示例图像的完整示例:

%# some sample images
I = imread('coins.png');
I_transp = imread('peppers.png');

%# create a gaussian mask for transparency
[r,c,~] = size(I_transp);
M = fspecial('gaussian', [r c], mean([r c]./5));
M = (M-min(M(:)))./range(M(:));

%# show overlayed images
figure, imshow(I, 'XData',[1 c], 'YData',[1 r]), hold on
hImg = imshow(I_transp);
set(hImg, 'AlphaData',M);

%# draw a rectangle
rectangle('Position',[355 220 100 100], 'LineWidth',2, 'EdgeColor','b');